Using of wavelet transform in the analysis of AE signals accompanying the process of epoxy resins electrical treeing

Abstract

The paper presents a computer application developed for analysis of acoustic emission signals accopanying the process of electric treeing occurring in polymeric materials, and in particular epoxy resins used as high-voltage solid insulation. A method for measuring, recording and registration of signals was presented. In particular,it is shown how the developed application uses wavelet transformation to remove noise from the recorded signal, and to carry out a time-frequency analysis of these signals. The results of the sample analysis of the recorded signals were also shown. Streszczenie. W artykule zaprezentowano aplikację komputerową opracowaną w celu analizy sygnałów emisji akustycznej towarzyszących procesowi drzewienia elektrycznego materiałów polimerowych, w szczególności żywic epoksydowych stosowanych jako wysokonapięciowa izolacja stała. Zaprezentowano sposób pomiaru, rejestracji i rejestracji sygnałów. W szczególności pokazano w jaki sposób opracowana aplikacja wykorzystuje transformację falkowa do usunięcia szumów z zarejestrowanego sygnału, a także do prowadzenia analizy czasowo-częstotliwościowej tych sygnałów. Pokazano również wyniki przykładowej analizy zarejestrowanych sygnałów. Analiza sygnałów emisji akustycznej towarzyszących procesowi drzewienia elektrycznego materiałów polimerowych Słowa kluczowe: transformata falkowa, drzewienie elektryczne; badania nieniszczące, izolacja wysokonapięciowa.

Influence of additional dielectric coatings on the electrode surfaces on selected parameters of acoustic emission signals in high-voltage gas insulation systems

“…• removing noise from signals (using wavelet transform), • calculation of selected parameters of AE signals [15,16].…”

“…This is the reason why the level of these discharges can be measured and analyzed on the basis of non-invasive methods, e.g., the Acoustic Emission (AE) method [7,[12][13][14]. This method is constantly developed, and thanks to increasingly efficient measuring equipment and advanced methods of analysis of recorded signals, its accuracy is constantly improving [15,16].…”

Application of Wavelet Transform to Damage Identification in the Steel Structure Elements

“…Then a method is sought, which could be considered universal, i.e., effective in the whole band of the registered signal. The solution may be to use a wavelet transform that meets these requirements [21,22].…”

“…As shown in work [21], the use of the wavelet transform is an effective method of noise removal and guarantees minimal information loss. The assumption of the algorithm is to minimize the mean square error.…”

Influence of defect in an excited steel plate on the results of time-frequency analysis

“…In order to examine the state of technical objects, their models are often used [1,2] and the characteristic values are analyzed [3,4]. Another advanced, non-invasive diagnostic methods used in this research work, is the acoustic emission method AE [5][6][7][8]. However, the global structural response may be insensitive to local small changes caused by defects, so if one doesn't want to use or doesn't have an information about an intact structure it is advisable to use e.g.…”